I'm usually prompted to buy a book in 3 different ways:
- I've got a very specific skill I'm working on and need the knowledge so I'll go looking for it
- I've received a recommendation while listening to something or while reading another book
- I'm walking through a book store looking for inspiration

When deciding:
- I don't read free chapters, but I might scan the table of contents
- Generally, I judge a book by its cover haha